For over a decade, the Precision Guided Munitions (PGM's) and other Electro-Optical Guided Munitions (EOGM's) have been plagued by the age-old problem of establishment and maintenance of boresight in addition to the stabilization of the line of sight in turbulent atmospheres, vibrating environments, and lightweight optical structures, especially in the cases where laser designators are utilized to define the aimpoint at the target plane. In principle, the concept of laser designation is well based in a theoretical and experimental sense; however, the reliable reduction to practical applications in the Army is continually plagued by the boresight and stabilization problem.
This patent disclosure offers a solution to this problem by describing a general concept of Target Loop Active Boresighting (TLAB) applicable to many systems, and offers a unique sensor/laser designator/filter construct that solves the boresight and line of sight stabilization problem. This concept contains numerous unique advantages that have never before been possible until the invention of this sensor system to be described under the sensor/designator/filter section of this disclosure.
Prior to the invention disclosure, it is appropriate to describe the concept of Target Loop Active Boresight (TLAB) to lay the groundwork for an understanding of the sensor/designator/filter combination. In any PGM or EOGM, the operating premise is one in which the target, its aimpoint, the laser designator, the guidance package of the PGM, and the flight trajectory of the PGM must all attain closure at the target's aimpoint. The principle is simple but existing systems are rendered less than highly reliable because of one missing item; i.e., the night viewer or forward looking infrared (FLIR) cannot establish target plane closure of the aimpoint and the designator because it cannot "see" the target and the designator on a single sensor. Therefore, if the sensor and the laser designator are out of alignment, the operator will direct the PGM to the wrong location. This disclosure describes an invention that eliminates these problems and, therefore, provides the solution to the implementation of a complete TLAB system, meanwhile offering simplicity and economy over existing systems that are plagued with the boresight problem because they cannot "see" all necessary target parameters in a single sensor.